1. Field of the Invention
The invention relates to a method for estimating the range of a motor vehicle by means of a quantity of energy that is carried along in the motor vehicle and can be detected. The invention also relates to a motor vehicle having a device for estimating range.
2. Description of the Related Art
DE 43 44 369 A1 discloses a method for consumption-oriented limitation of the driving performance, in particular for electric vehicles. The method assists the driver in utilizing the energy supply that is carried along. A permissible route consumption, which is related to the residual distance, is calculated continually on the basis of the existing energy supply. A preset value then is determined from the permissible route consumption taking into account running resistances and actuates a device for limiting the driving performance.
U.S. Pat. No. 5,487,002 also discloses a method for estimating range in electric vehicles as a function of a wide variety of parameters such as running resistances, running profiles or the state of charge of a vehicle battery.
In contrast to conventional gasoline stations, there is still only been a sparse network of recharging points available for electric vehicles. Therefore, becoming inadvertently stuck on the open road is extremely inconvenient for electric vehicles. Merely managing to reach a recharging point is not desirable for electric vehicles because a recharging process takes a considerable time and delays the ongoing journey. For these reasons, it may be beneficial under certain circumstances to apportion the energy supply by selectively throttling driving style so that the energy supply that is still available in the motor vehicle is sufficient at least to reach the selected destination. Moreover, a driver of an electric vehicle desirably should be able to estimate the maximum range that is available if no specific destination has been set.
The invention is concerned with a method for improved energy management.